I. Field of the Invention
The invention relates to a machine for agricultural irrigation and is particularly concerned with an irrigation machine of the hose-drum type.
II. Description of the Prior Art
In previously known irrigation machines of the hose type, a hose-drum is mounted on a chassis or supporting vehicle, the hose-drum has a flexible hose wound thereon and supplied at the inner end of the hose from a source of water, the outer end of the hose being attached to an irrigation nozzle or gun mounted on a trolley or sledge. By winding-in the hose on the drum while water is being supplied through the hose, the irrigation nozzle or gun discharges water while the trolley or sledge with the nozzle or gun thereon is pulled by the hose towards the chassis or supporting vehicle on which the drum is mounted.
In conventional hose-drum machines of the foregoing type it is conventional to mount the drum for rotation about a central horizontal shaft supported at its end on brackets or stanchions, which are either mounted directly on the chassis or supporting vehicle, or are mounted on a turret or platform supported on the chassis or vehicle for turning about a vertical axis. Such machines have a number of disadvantages.
The first disadvantage is that as the drum is of large diameter and axial length in order to accommodate a long length of hose, the drum and hose, particularly when the latter is running full of water, are extremely heavy. Therefore the supporting brackets and turret, where the drum is mounted on a turret, are of heavy construction and extend above the chassis. The combined centre of gravity of the hose-drum and supporting structure is therefore at a substantial height above the chassis. There is therefore a risk that the machine could topple over, particularly where it is being transported over rough ground. In addition, this risk of toppling over is present during operation, that is during watering, since the tension of the hose is pulling the trolley or sledge is applied at the height of the shaft of the drum. This tensile force is considerable, taking into account the length and diameter of the hose, the weight of the water therein and the frictional forces between the hose and the ground. Therefore the moment of this tensile force applied by the hose to the drum at the height of the axis of the shaft also tends to topple the chassis.
Another disadvantage of known hose-drum machines is that the hose, although it is wound-up from the bottom of the drum, still has to be raised during winding due to the drum being mounted above the chassis, particularly where the drum is mounted on a turret. This also results in a tendency for the machine to be unstable.
Yet another disadvantage is that the drum and its supporting shaft are usually formed as an assembly which cannot readily be removed from the chassis or turret, for example, to facilitate transport of the machine.
The invention has as its object the avoidance of these and other disadvantages.